如何运用PHP转义符解决代码转换问题

<ol class="dp-xml">
<li class="alt"><span><span class="tag"><strong><font color="#006699"></font></strong></span><span> </span></span></li>
<li class=""><span>//--标题,名字等字段入库处理(去首尾空格)  </span></li>
<li class="alt"><span>function trans_string_trim($str) {  </span></li>
<li class="">
<span>$</span><span class="attribute"><font color="#ff0000">str</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">trim</font></span><span>($str);  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">str</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">eregi_replace</font></span><span>("'","''",$str);  </span>
</li>
<li class="">
<span>$</span><span class="attribute"><font color="#ff0000">str</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">stripslashes</font></span><span>($str);  </span>
</li>
<li class="alt"><span>return $str;  </span></li>
<li class=""><span>}  </span></li>
<li class="alt"><span> </span></li>
<li class=""><span>//--文章入库处理，即textarea字段；  </span></li>
<li class="alt"><span>function trans_string($str) {  </span></li>
<li class="">
<span>$</span><span class="attribute"><font color="#ff0000">str</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">eregi_replace</font></span><span>("'","''",$str);  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">str</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">stripslashes</font></span><span>($str);  </span>
</li>
<li class=""><span>return $str;  </span></li>
<li class="alt"><span>}  </span></li>
<li class=""><span> </span></li>
<li class="alt"><span>//--从库中显示在表单中；在text中以trans转换,在textarea中,无需转换,直接显示  </span></li>
<li class=""><span> </span></li>
<li class="alt"><span>//--显示在WEB页面，过滤HTML代码；包括链接地址  </span></li>
<li class=""><span>function trans($string) {  </span></li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">htmlspecialchars</font></span><span>($string);  </span>
</li>
<li class="">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">ereg_replace</font></span><span>(chr(10),"</span><strong><font color="#006699"><span class="tag"><span class="tag-name">br</span><span class="tag">></span></span></font></strong><span>",$string);  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">ereg_replace</font></span><span>(chr(32)," ",$string);  </span>
</li>
<li class=""><span>return $string;  </span></li>
<li class="alt"><span>}  </span></li>
<li class=""><span> </span></li>
<li class="alt"><span>//--显示在WEB页面，不过滤HTML代码；  </span></li>
<li class=""><span>function trans_web($string) {  </span></li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">ereg_replace</font></span><span>(chr(10),"</span><strong><font color="#006699"><span class="tag"><span class="tag-name">br</span><span class="tag">></span></span></font></strong><span>",$string);  </span>
</li>
<li class="">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">ereg_replace</font></span><span>(chr(32)," ",$string);  </span>
</li>
<li class="alt"><span>return $string;  </span></li>
<li class=""><span>}  </span></li>
<li class="alt"><span> </span></li>
<li class=""><span>//--显示在WEB页面，过滤HTML代码及头尾空格,主要用于显示用户昵称  </span></li>
<li class="alt"><span>function trans_trim($string) {  </span></li>
<li class="">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">trim</font></span><span>($string);  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">htmlspecialchars</font></span><span>($string);  </span>
</li>
<li class="">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">ereg_replace</font></span><span>(chr(10),"</span><strong><font color="#006699"><span class="tag"><span class="tag-name">br</span><span class="tag">></span></span></font></strong><span>",$string);  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">ereg_replace</font></span><span>(chr(32)," ",$string);  </span>
</li>
<li class=""><span>return $string;  </span></li>
<li class="alt"><span>}  </span></li>
<li class=""><span> </span></li>
<li class="alt"><span>//--显示在span中；  </span></li>
<li class=""><span>function trans_span($string) {  </span></li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">ereg_replace</font></span><span>(chr(10),"n",$string);  </span>
</li>
<li class="">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">ereg_replace</font></span><span>(chr(32)," ",$string);  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">string</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">ereg_replace</font></span><span>('"',""",$string);  </span>
</li>
<li class=""><span>return $string;  </span></li>
<li class="alt"><span>}  </span></li>
<li class=""><span> </span></li>
<li class="alt"><span>//--在WEB上显示cookie,过滤html  </span></li>
<li class=""><span>function trans_cookie($str) {  </span></li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">str</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">trans</font></span><span>($str);  </span>
</li>
<li class="">
<span>$</span><span class="attribute"><font color="#ff0000">str</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">stripslashes</font></span><span>($str);  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">str</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">eregi_replace</font></span><span>("''","'",$str);  </span>
</li>
<li class=""><span>return $str;  </span></li>
<li class="alt"><span>}  </span></li>
<li class="">
<span></span><span class="tag"><strong><font color="#006699">?></font></strong></span><span> </span>
</li>
</ol>